net/slirp.c

   1 /*
   2  * QEMU System Emulator
   3  *
   4  * Copyright (c) 2003-2008 Fabrice Bellard
   5  *
   6  * Permission is hereby granted, free of charge, to any person obtaining a copy
   7  * of this software and associated documentation files (the "Software"), to deal
   8  * in the Software without restriction, including without limitation the rights
   9  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  10  * copies of the Software, and to permit persons to whom the Software is
  11  * furnished to do so, subject to the following conditions:
  12  *
  13  * The above copyright notice and this permission notice shall be included in
  14  * all copies or substantial portions of the Software.
  15  *
  16  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  17  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  18  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
  19  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  20  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  21  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  22  * THE SOFTWARE.
  23  */
  24
  25 #include "qemu/osdep.h"
  26 #include "qemu/log.h"
  27 #include "net/slirp.h"
  28
  29
  30 #ifndef _WIN32
  31 #include <pwd.h>
  32 #include <sys/wait.h>
  33 #endif
  34 #include "net/net.h"
  35 #include "clients.h"
  36 #include "hub.h"
  37 #include "monitor/monitor.h"
  38 #include "qemu/error-report.h"
  39 #include "qemu/sockets.h"
  40 #include <libslirp.h>
  41 #include "chardev/char-fe.h"
  42 #include "sysemu/sysemu.h"
  43 #include "qemu/cutils.h"
  44 #include "qapi/error.h"
  45 #include "qapi/qmp/qdict.h"
  46 #include "util.h"
  47 #include "migration/register.h"
  48 #include "migration/qemu-file-types.h"
  49
  50 static int get_str_sep(char *buf, int buf_size, const char **pp, int sep)
  51 {
  52     const char *p, *p1;
  53     int len;
  54     p = *pp;
  55     p1 = strchr(p, sep);
  56     if (!p1)
  57         return -1;
  58     len = p1 - p;
  59     p1++;
  60     if (buf_size > 0) {
  61         if (len > buf_size - 1)
  62             len = buf_size - 1;
  63         memcpy(buf, p, len);
  64         buf[len] = '\0';
  65     }
  66     *pp = p1;
  67     return 0;
  68 }
  69
  70 /* slirp network adapter */
  71
  72 #define SLIRP_CFG_HOSTFWD 1
  73
  74 struct slirp_config_str {
  75     struct slirp_config_str *next;
  76     int flags;
  77     char str[1024];
  78 };
  79
  80 struct GuestFwd {
  81     CharBackend hd;
  82     struct in_addr server;
  83     int port;
  84     Slirp *slirp;
  85 };
  86
  87 typedef struct SlirpState {
  88     NetClientState nc;
  89     QTAILQ_ENTRY(SlirpState) entry;
  90     Slirp *slirp;
  91     Notifier poll_notifier;
  92     Notifier exit_notifier;
  93 #ifndef _WIN32
  94     gchar *smb_dir;
  95 #endif
  96     GSList *fwd;
  97 } SlirpState;
  98
  99 static struct slirp_config_str *slirp_configs;
 100 static QTAILQ_HEAD(, SlirpState) slirp_stacks =
 101     QTAILQ_HEAD_INITIALIZER(slirp_stacks);
 102
 103 static int slirp_hostfwd(SlirpState *s, const char *redir_str, Error **errp);
 104 static int slirp_guestfwd(SlirpState *s, const char *config_str, Error **errp);
 105
 106 #ifndef _WIN32
 107 static int slirp_smb(SlirpState *s, const char *exported_dir,
 108                      struct in_addr vserver_addr, Error **errp);
 109 static void slirp_smb_cleanup(SlirpState *s);
 110 #else
 111 static inline void slirp_smb_cleanup(SlirpState *s) { }
 112 #endif
 113
 114 static ssize_t net_slirp_send_packet(const void *pkt, size_t pkt_len,
 115                                      void *opaque)
 116 {
 117     SlirpState *s = opaque;
 118
 119     return qemu_send_packet(&s->nc, pkt, pkt_len);
 120 }
 121
 122 static ssize_t net_slirp_receive(NetClientState *nc, const uint8_t *buf, size_t size)
 123 {
 124     SlirpState *s = DO_UPCAST(SlirpState, nc, nc);
 125
 126     slirp_input(s->slirp, buf, size);
 127
 128     return size;
 129 }
 130
 131 static void slirp_smb_exit(Notifier *n, void *data)
 132 {
 133     SlirpState *s = container_of(n, SlirpState, exit_notifier);
 134     slirp_smb_cleanup(s);
 135 }
 136
 137 static void slirp_free_fwd(gpointer data)
 138 {
 139     struct GuestFwd *fwd = data;
 140
 141     qemu_chr_fe_deinit(&fwd->hd, true);
 142     g_free(data);
 143 }
 144
 145 static void net_slirp_cleanup(NetClientState *nc)
 146 {
 147     SlirpState *s = DO_UPCAST(SlirpState, nc, nc);
 148
 149     g_slist_free_full(s->fwd, slirp_free_fwd);
 150     main_loop_poll_remove_notifier(&s->poll_notifier);
 151     unregister_savevm(NULL, "slirp", s->slirp);
 152     slirp_cleanup(s->slirp);
 153     if (s->exit_notifier.notify) {
 154         qemu_remove_exit_notifier(&s->exit_notifier);
 155     }
 156     slirp_smb_cleanup(s);
 157     QTAILQ_REMOVE(&slirp_stacks, s, entry);
 158 }
 159
 160 static NetClientInfo net_slirp_info = {
 161     .type = NET_CLIENT_DRIVER_USER,
 162     .size = sizeof(SlirpState),
 163     .receive = net_slirp_receive,
 164     .cleanup = net_slirp_cleanup,
 165 };
 166
 167 static void net_slirp_guest_error(const char *msg, void *opaque)
 168 {
 169     qemu_log_mask(LOG_GUEST_ERROR, "%s", msg);
 170 }
 171
 172 static int64_t net_slirp_clock_get_ns(void *opaque)
 173 {
 174     return qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
 175 }
 176
 177 static void *net_slirp_timer_new(SlirpTimerCb cb,
 178                                  void *cb_opaque, void *opaque)
 179 {
 180     return timer_new_full(NULL, QEMU_CLOCK_VIRTUAL,
 181                           SCALE_MS, QEMU_TIMER_ATTR_EXTERNAL,
 182                           cb, cb_opaque);
 183 }
 184
 185 static void net_slirp_timer_free(void *timer, void *opaque)
 186 {
 187     timer_del(timer);
 188     timer_free(timer);
 189 }
 190
 191 static void net_slirp_timer_mod(void *timer, int64_t expire_timer,
 192                                 void *opaque)
 193 {
 194     timer_mod(timer, expire_timer);
 195 }
 196
 197 static void net_slirp_register_poll_fd(int fd, void *opaque)
 198 {
 199     qemu_fd_register(fd);
 200 }
 201
 202 static void net_slirp_unregister_poll_fd(int fd, void *opaque)
 203 {
 204     /* no qemu_fd_unregister */
 205 }
 206
 207 static void net_slirp_notify(void *opaque)
 208 {
 209     qemu_notify_event();
 210 }
 211
 212 static const SlirpCb slirp_cb = {
 213     .send_packet = net_slirp_send_packet,
 214     .guest_error = net_slirp_guest_error,
 215     .clock_get_ns = net_slirp_clock_get_ns,
 216     .timer_new = net_slirp_timer_new,
 217     .timer_free = net_slirp_timer_free,
 218     .timer_mod = net_slirp_timer_mod,
 219     .register_poll_fd = net_slirp_register_poll_fd,
 220     .unregister_poll_fd = net_slirp_unregister_poll_fd,
 221     .notify = net_slirp_notify,
 222 };
 223
 224 static int slirp_poll_to_gio(int events)
 225 {
 226     int ret = 0;
 227
 228     if (events & SLIRP_POLL_IN) {
 229         ret |= G_IO_IN;
 230     }
 231     if (events & SLIRP_POLL_OUT) {
 232         ret |= G_IO_OUT;
 233     }
 234     if (events & SLIRP_POLL_PRI) {
 235         ret |= G_IO_PRI;
 236     }
 237     if (events & SLIRP_POLL_ERR) {
 238         ret |= G_IO_ERR;
 239     }
 240     if (events & SLIRP_POLL_HUP) {
 241         ret |= G_IO_HUP;
 242     }
 243
 244     return ret;
 245 }
 246
 247 static int net_slirp_add_poll(int fd, int events, void *opaque)
 248 {
 249     GArray *pollfds = opaque;
 250     GPollFD pfd = {
 251         .fd = fd,
 252         .events = slirp_poll_to_gio(events),
 253     };
 254     int idx = pollfds->len;
 255     g_array_append_val(pollfds, pfd);
 256     return idx;
 257 }
 258
 259 static int slirp_gio_to_poll(int events)
 260 {
 261     int ret = 0;
 262
 263     if (events & G_IO_IN) {
 264         ret |= SLIRP_POLL_IN;
 265     }
 266     if (events & G_IO_OUT) {
 267         ret |= SLIRP_POLL_OUT;
 268     }
 269     if (events & G_IO_PRI) {
 270         ret |= SLIRP_POLL_PRI;
 271     }
 272     if (events & G_IO_ERR) {
 273         ret |= SLIRP_POLL_ERR;
 274     }
 275     if (events & G_IO_HUP) {
 276         ret |= SLIRP_POLL_HUP;
 277     }
 278
 279     return ret;
 280 }
 281
 282 static int net_slirp_get_revents(int idx, void *opaque)
 283 {
 284     GArray *pollfds = opaque;
 285
 286     return slirp_gio_to_poll(g_array_index(pollfds, GPollFD, idx).revents);
 287 }
 288
 289 static void net_slirp_poll_notify(Notifier *notifier, void *data)
 290 {
 291     MainLoopPoll *poll = data;
 292     SlirpState *s = container_of(notifier, SlirpState, poll_notifier);
 293
 294     switch (poll->state) {
 295     case MAIN_LOOP_POLL_FILL:
 296         slirp_pollfds_fill(s->slirp, &poll->timeout,
 297                            net_slirp_add_poll, poll->pollfds);
 298         break;
 299     case MAIN_LOOP_POLL_OK:
 300     case MAIN_LOOP_POLL_ERR:
 301         slirp_pollfds_poll(s->slirp, poll->state == MAIN_LOOP_POLL_ERR,
 302                            net_slirp_get_revents, poll->pollfds);
 303         break;
 304     default:
 305         g_assert_not_reached();
 306     }
 307 }
 308
 309 static ssize_t
 310 net_slirp_stream_read(void *buf, size_t size, void *opaque)
 311 {
 312     QEMUFile *f = opaque;
 313
 314     return qemu_get_buffer(f, buf, size);
 315 }
 316
 317 static ssize_t
 318 net_slirp_stream_write(const void *buf, size_t size, void *opaque)
 319 {
 320     QEMUFile *f = opaque;
 321
 322     qemu_put_buffer(f, buf, size);
 323     if (qemu_file_get_error(f)) {
 324         return -1;
 325     }
 326
 327     return size;
 328 }
 329
 330 static int net_slirp_state_load(QEMUFile *f, void *opaque, int version_id)
 331 {
 332     Slirp *slirp = opaque;
 333
 334     return slirp_state_load(slirp, version_id, net_slirp_stream_read, f);
 335 }
 336
 337 static void net_slirp_state_save(QEMUFile *f, void *opaque)
 338 {
 339     Slirp *slirp = opaque;
 340
 341     slirp_state_save(slirp, net_slirp_stream_write, f);
 342 }
 343
 344 static SaveVMHandlers savevm_slirp_state = {
 345     .save_state = net_slirp_state_save,
 346     .load_state = net_slirp_state_load,
 347 };
 348
 349 static int net_slirp_init(NetClientState *peer, const char *model,
 350                           const char *name, int restricted,
 351                           bool ipv4, const char *vnetwork, const char *vhost,
 352                           bool ipv6, const char *vprefix6, int vprefix6_len,
 353                           const char *vhost6,
 354                           const char *vhostname, const char *tftp_export,
 355                           const char *bootfile, const char *vdhcp_start,
 356                           const char *vnameserver, const char *vnameserver6,
 357                           const char *smb_export, const char *vsmbserver,
 358                           const char **dnssearch, const char *vdomainname,
 359                           const char *tftp_server_name,
 360                           Error **errp)
 361 {
 362     /* default settings according to historic slirp */
 363     struct in_addr net  = { .s_addr = htonl(0x0a000200) }; /* 10.0.2.0 */
 364     struct in_addr mask = { .s_addr = htonl(0xffffff00) }; /* 255.255.255.0 */
 365     struct in_addr host = { .s_addr = htonl(0x0a000202) }; /* 10.0.2.2 */
 366     struct in_addr dhcp = { .s_addr = htonl(0x0a00020f) }; /* 10.0.2.15 */
 367     struct in_addr dns  = { .s_addr = htonl(0x0a000203) }; /* 10.0.2.3 */
 368     struct in6_addr ip6_prefix;
 369     struct in6_addr ip6_host;
 370     struct in6_addr ip6_dns;
 371 #ifndef _WIN32
 372     struct in_addr smbsrv = { .s_addr = 0 };
 373 #endif
 374     NetClientState *nc;
 375     SlirpState *s;
 376     char buf[20];
 377     uint32_t addr;
 378     int shift;
 379     char *end;
 380     struct slirp_config_str *config;
 381
 382     if (!ipv4 && (vnetwork || vhost || vnameserver)) {
 383         error_setg(errp, "IPv4 disabled but netmask/host/dns provided");
 384         return -1;
 385     }
 386
 387     if (!ipv6 && (vprefix6 || vhost6 || vnameserver6)) {
 388         error_setg(errp, "IPv6 disabled but prefix/host6/dns6 provided");
 389         return -1;
 390     }
 391
 392     if (!ipv4 && !ipv6) {
 393         /* It doesn't make sense to disable both */
 394         error_setg(errp, "IPv4 and IPv6 disabled");
 395         return -1;
 396     }
 397
 398     if (vnetwork) {
 399         if (get_str_sep(buf, sizeof(buf), &vnetwork, '/') < 0) {
 400             if (!inet_aton(vnetwork, &net)) {
 401                 error_setg(errp, "Failed to parse netmask");
 402                 return -1;
 403             }
 404             addr = ntohl(net.s_addr);
 405             if (!(addr & 0x80000000)) {
 406                 mask.s_addr = htonl(0xff000000); /* class A */
 407             } else if ((addr & 0xfff00000) == 0xac100000) {
 408                 mask.s_addr = htonl(0xfff00000); /* priv. 172.16.0.0/12 */
 409             } else if ((addr & 0xc0000000) == 0x80000000) {
 410                 mask.s_addr = htonl(0xffff0000); /* class B */
 411             } else if ((addr & 0xffff0000) == 0xc0a80000) {
 412                 mask.s_addr = htonl(0xffff0000); /* priv. 192.168.0.0/16 */
 413             } else if ((addr & 0xffff0000) == 0xc6120000) {
 414                 mask.s_addr = htonl(0xfffe0000); /* tests 198.18.0.0/15 */
 415             } else if ((addr & 0xe0000000) == 0xe0000000) {
 416                 mask.s_addr = htonl(0xffffff00); /* class C */
 417             } else {
 418                 mask.s_addr = htonl(0xfffffff0); /* multicast/reserved */
 419             }
 420         } else {
 421             if (!inet_aton(buf, &net)) {
 422                 error_setg(errp, "Failed to parse netmask");
 423                 return -1;
 424             }
 425             shift = strtol(vnetwork, &end, 10);
 426             if (*end != '\0') {
 427                 if (!inet_aton(vnetwork, &mask)) {
 428                     error_setg(errp,
 429                                "Failed to parse netmask (trailing chars)");
 430                     return -1;
 431                 }
 432             } else if (shift < 4 || shift > 32) {
 433                 error_setg(errp,
 434                            "Invalid netmask provided (must be in range 4-32)");
 435                 return -1;
 436             } else {
 437                 mask.s_addr = htonl(0xffffffff << (32 - shift));
 438             }
 439         }
 440         net.s_addr &= mask.s_addr;
 441         host.s_addr = net.s_addr | (htonl(0x0202) & ~mask.s_addr);
 442         dhcp.s_addr = net.s_addr | (htonl(0x020f) & ~mask.s_addr);
 443         dns.s_addr  = net.s_addr | (htonl(0x0203) & ~mask.s_addr);
 444     }
 445
 446     if (vhost && !inet_aton(vhost, &host)) {
 447         error_setg(errp, "Failed to parse host");
 448         return -1;
 449     }
 450     if ((host.s_addr & mask.s_addr) != net.s_addr) {
 451         error_setg(errp, "Host doesn't belong to network");
 452         return -1;
 453     }
 454
 455     if (vnameserver && !inet_aton(vnameserver, &dns)) {
 456         error_setg(errp, "Failed to parse DNS");
 457         return -1;
 458     }
 459     if (restricted && (dns.s_addr & mask.s_addr) != net.s_addr) {
 460         error_setg(errp, "DNS doesn't belong to network");
 461         return -1;
 462     }
 463     if (dns.s_addr == host.s_addr) {
 464         error_setg(errp, "DNS must be different from host");
 465         return -1;
 466     }
 467
 468     if (vdhcp_start && !inet_aton(vdhcp_start, &dhcp)) {
 469         error_setg(errp, "Failed to parse DHCP start address");
 470         return -1;
 471     }
 472     if ((dhcp.s_addr & mask.s_addr) != net.s_addr) {
 473         error_setg(errp, "DHCP doesn't belong to network");
 474         return -1;
 475     }
 476     if (dhcp.s_addr == host.s_addr || dhcp.s_addr == dns.s_addr) {
 477         error_setg(errp, "DNS must be different from host and DNS");
 478         return -1;
 479     }
 480
 481 #ifndef _WIN32
 482     if (vsmbserver && !inet_aton(vsmbserver, &smbsrv)) {
 483         error_setg(errp, "Failed to parse SMB address");
 484         return -1;
 485     }
 486 #endif
 487
 488     if (!vprefix6) {
 489         vprefix6 = "fec0::";
 490     }
 491     if (!inet_pton(AF_INET6, vprefix6, &ip6_prefix)) {
 492         error_setg(errp, "Failed to parse IPv6 prefix");
 493         return -1;
 494     }
 495
 496     if (!vprefix6_len) {
 497         vprefix6_len = 64;
 498     }
 499     if (vprefix6_len < 0 || vprefix6_len > 126) {
 500         error_setg(errp,
 501                    "Invalid IPv6 prefix provided "
 502                    "(IPv6 prefix length must be between 0 and 126)");
 503         return -1;
 504     }
 505
 506     if (vhost6) {
 507         if (!inet_pton(AF_INET6, vhost6, &ip6_host)) {
 508             error_setg(errp, "Failed to parse IPv6 host");
 509             return -1;
 510         }
 511         if (!in6_equal_net(&ip6_prefix, &ip6_host, vprefix6_len)) {
 512             error_setg(errp, "IPv6 Host doesn't belong to network");
 513             return -1;
 514         }
 515     } else {
 516         ip6_host = ip6_prefix;
 517         ip6_host.s6_addr[15] |= 2;
 518     }
 519
 520     if (vnameserver6) {
 521         if (!inet_pton(AF_INET6, vnameserver6, &ip6_dns)) {
 522             error_setg(errp, "Failed to parse IPv6 DNS");
 523             return -1;
 524         }
 525         if (restricted && !in6_equal_net(&ip6_prefix, &ip6_dns, vprefix6_len)) {
 526             error_setg(errp, "IPv6 DNS doesn't belong to network");
 527             return -1;
 528         }
 529     } else {
 530         ip6_dns = ip6_prefix;
 531         ip6_dns.s6_addr[15] |= 3;
 532     }
 533
 534     if (vdomainname && !*vdomainname) {
 535         error_setg(errp, "'domainname' parameter cannot be empty");
 536         return -1;
 537     }
 538
 539     if (vdomainname && strlen(vdomainname) > 255) {
 540         error_setg(errp, "'domainname' parameter cannot exceed 255 bytes");
 541         return -1;
 542     }
 543
 544     if (vhostname && strlen(vhostname) > 255) {
 545         error_setg(errp, "'vhostname' parameter cannot exceed 255 bytes");
 546         return -1;
 547     }
 548
 549     if (tftp_server_name && strlen(tftp_server_name) > 255) {
 550         error_setg(errp, "'tftp-server-name' parameter cannot exceed 255 bytes");
 551         return -1;
 552     }
 553
 554     nc = qemu_new_net_client(&net_slirp_info, peer, model, name);
 555
 556     snprintf(nc->info_str, sizeof(nc->info_str),
 557              "net=%s,restrict=%s", inet_ntoa(net),
 558              restricted ? "on" : "off");
 559
 560     s = DO_UPCAST(SlirpState, nc, nc);
 561
 562     s->slirp = slirp_init(restricted, ipv4, net, mask, host,
 563                           ipv6, ip6_prefix, vprefix6_len, ip6_host,
 564                           vhostname, tftp_server_name,
 565                           tftp_export, bootfile, dhcp,
 566                           dns, ip6_dns, dnssearch, vdomainname,
 567                           &slirp_cb, s);
 568     QTAILQ_INSERT_TAIL(&slirp_stacks, s, entry);
 569
 570     /*
 571      * Make sure the current bitstream version of slirp is 4, to avoid
 572      * QEMU migration incompatibilities, if upstream slirp bumped the
 573      * version.
 574      *
 575      * FIXME: use bitfields of features? teach libslirp to save with
 576      * specific version?
 577      */
 578     g_assert(slirp_state_version() == 4);
 579     register_savevm_live("slirp", 0, slirp_state_version(),
 580                          &savevm_slirp_state, s->slirp);
 581
 582     s->poll_notifier.notify = net_slirp_poll_notify;
 583     main_loop_poll_add_notifier(&s->poll_notifier);
 584
 585     for (config = slirp_configs; config; config = config->next) {
 586         if (config->flags & SLIRP_CFG_HOSTFWD) {
 587             if (slirp_hostfwd(s, config->str, errp) < 0) {
 588                 goto error;
 589             }
 590         } else {
 591             if (slirp_guestfwd(s, config->str, errp) < 0) {
 592                 goto error;
 593             }
 594         }
 595     }
 596 #ifndef _WIN32
 597     if (smb_export) {
 598         if (slirp_smb(s, smb_export, smbsrv, errp) < 0) {
 599             goto error;
 600         }
 601     }
 602 #endif
 603
 604     s->exit_notifier.notify = slirp_smb_exit;
 605     qemu_add_exit_notifier(&s->exit_notifier);
 606     return 0;
 607
 608 error:
 609     qemu_del_net_client(nc);
 610     return -1;
 611 }
 612
 613 static SlirpState *slirp_lookup(Monitor *mon, const char *id)
 614 {
 615     if (id) {
 616         NetClientState *nc = qemu_find_netdev(id);
 617         if (!nc) {
 618             monitor_printf(mon, "unrecognized netdev id '%s'\n", id);
 619             return NULL;
 620         }
 621         if (strcmp(nc->model, "user")) {
 622             monitor_printf(mon, "invalid device specified\n");
 623             return NULL;
 624         }
 625         return DO_UPCAST(SlirpState, nc, nc);
 626     } else {
 627         if (QTAILQ_EMPTY(&slirp_stacks)) {
 628             monitor_printf(mon, "user mode network stack not in use\n");
 629             return NULL;
 630         }
 631         return QTAILQ_FIRST(&slirp_stacks);
 632     }
 633 }
 634
 635 void hmp_hostfwd_remove(Monitor *mon, const QDict *qdict)
 636 {
 637     struct in_addr host_addr = { .s_addr = INADDR_ANY };
 638     int host_port;
 639     char buf[256];
 640     const char *src_str, *p;
 641     SlirpState *s;
 642     int is_udp = 0;
 643     int err;
 644     const char *arg1 = qdict_get_str(qdict, "arg1");
 645     const char *arg2 = qdict_get_try_str(qdict, "arg2");
 646
 647     if (arg2) {
 648         s = slirp_lookup(mon, arg1);
 649         src_str = arg2;
 650     } else {
 651         s = slirp_lookup(mon, NULL);
 652         src_str = arg1;
 653     }
 654     if (!s) {
 655         return;
 656     }
 657
 658     p = src_str;
 659     if (!p || get_str_sep(buf, sizeof(buf), &p, ':') < 0) {
 660         goto fail_syntax;
 661     }
 662
 663     if (!strcmp(buf, "tcp") || buf[0] == '\0') {
 664         is_udp = 0;
 665     } else if (!strcmp(buf, "udp")) {
 666         is_udp = 1;
 667     } else {
 668         goto fail_syntax;
 669     }
 670
 671     if (get_str_sep(buf, sizeof(buf), &p, ':') < 0) {
 672         goto fail_syntax;
 673     }
 674     if (buf[0] != '\0' && !inet_aton(buf, &host_addr)) {
 675         goto fail_syntax;
 676     }
 677
 678     if (qemu_strtoi(p, NULL, 10, &host_port)) {
 679         goto fail_syntax;
 680     }
 681
 682     err = slirp_remove_hostfwd(s->slirp, is_udp, host_addr, host_port);
 683
 684     monitor_printf(mon, "host forwarding rule for %s %s\n", src_str,
 685                    err ? "not found" : "removed");
 686     return;
 687
 688  fail_syntax:
 689     monitor_printf(mon, "invalid format\n");
 690 }
 691
 692 static int slirp_hostfwd(SlirpState *s, const char *redir_str, Error **errp)
 693 {
 694     struct in_addr host_addr = { .s_addr = INADDR_ANY };
 695     struct in_addr guest_addr = { .s_addr = 0 };
 696     int host_port, guest_port;
 697     const char *p;
 698     char buf[256];
 699     int is_udp;
 700     char *end;
 701     const char *fail_reason = "Unknown reason";
 702
 703     p = redir_str;
 704     if (!p || get_str_sep(buf, sizeof(buf), &p, ':') < 0) {
 705         fail_reason = "No : separators";
 706         goto fail_syntax;
 707     }
 708     if (!strcmp(buf, "tcp") || buf[0] == '\0') {
 709         is_udp = 0;
 710     } else if (!strcmp(buf, "udp")) {
 711         is_udp = 1;
 712     } else {
 713         fail_reason = "Bad protocol name";
 714         goto fail_syntax;
 715     }
 716
 717     if (get_str_sep(buf, sizeof(buf), &p, ':') < 0) {
 718         fail_reason = "Missing : separator";
 719         goto fail_syntax;
 720     }
 721     if (buf[0] != '\0' && !inet_aton(buf, &host_addr)) {
 722         fail_reason = "Bad host address";
 723         goto fail_syntax;
 724     }
 725
 726     if (get_str_sep(buf, sizeof(buf), &p, '-') < 0) {
 727         fail_reason = "Bad host port separator";
 728         goto fail_syntax;
 729     }
 730     host_port = strtol(buf, &end, 0);
 731     if (*end != '\0' || host_port < 0 || host_port > 65535) {
 732         fail_reason = "Bad host port";
 733         goto fail_syntax;
 734     }
 735
 736     if (get_str_sep(buf, sizeof(buf), &p, ':') < 0) {
 737         fail_reason = "Missing guest address";
 738         goto fail_syntax;
 739     }
 740     if (buf[0] != '\0' && !inet_aton(buf, &guest_addr)) {
 741         fail_reason = "Bad guest address";
 742         goto fail_syntax;
 743     }
 744
 745     guest_port = strtol(p, &end, 0);
 746     if (*end != '\0' || guest_port < 1 || guest_port > 65535) {
 747         fail_reason = "Bad guest port";
 748         goto fail_syntax;
 749     }
 750
 751     if (slirp_add_hostfwd(s->slirp, is_udp, host_addr, host_port, guest_addr,
 752                           guest_port) < 0) {
 753         error_setg(errp, "Could not set up host forwarding rule '%s'",
 754                    redir_str);
 755         return -1;
 756     }
 757     return 0;
 758
 759  fail_syntax:
 760     error_setg(errp, "Invalid host forwarding rule '%s' (%s)", redir_str,
 761                fail_reason);
 762     return -1;
 763 }
 764
 765 void hmp_hostfwd_add(Monitor *mon, const QDict *qdict)
 766 {
 767     const char *redir_str;
 768     SlirpState *s;
 769     const char *arg1 = qdict_get_str(qdict, "arg1");
 770     const char *arg2 = qdict_get_try_str(qdict, "arg2");
 771
 772     if (arg2) {
 773         s = slirp_lookup(mon, arg1);
 774         redir_str = arg2;
 775     } else {
 776         s = slirp_lookup(mon, NULL);
 777         redir_str = arg1;
 778     }
 779     if (s) {
 780         Error *err = NULL;
 781         if (slirp_hostfwd(s, redir_str, &err) < 0) {
 782             error_report_err(err);
 783         }
 784     }
 785
 786 }
 787
 788 #ifndef _WIN32
 789
 790 /* automatic user mode samba server configuration */
 791 static void slirp_smb_cleanup(SlirpState *s)
 792 {
 793     int ret;
 794
 795     if (s->smb_dir) {
 796         gchar *cmd = g_strdup_printf("rm -rf %s", s->smb_dir);
 797         ret = system(cmd);
 798         if (ret == -1 || !WIFEXITED(ret)) {
 799             error_report("'%s' failed.", cmd);
 800         } else if (WEXITSTATUS(ret)) {
 801             error_report("'%s' failed. Error code: %d",
 802                          cmd, WEXITSTATUS(ret));
 803         }
 804         g_free(cmd);
 805         g_free(s->smb_dir);
 806         s->smb_dir = NULL;
 807     }
 808 }
 809
 810 static int slirp_smb(SlirpState* s, const char *exported_dir,
 811                      struct in_addr vserver_addr, Error **errp)
 812 {
 813     char *smb_conf;
 814     char *smb_cmdline;
 815     struct passwd *passwd;
 816     FILE *f;
 817
 818     passwd = getpwuid(geteuid());
 819     if (!passwd) {
 820         error_setg(errp, "Failed to retrieve user name");
 821         return -1;
 822     }
 823
 824     if (access(CONFIG_SMBD_COMMAND, F_OK)) {
 825         error_setg(errp, "Could not find '%s', please install it",
 826                    CONFIG_SMBD_COMMAND);
 827         return -1;
 828     }
 829
 830     if (access(exported_dir, R_OK | X_OK)) {
 831         error_setg(errp, "Error accessing shared directory '%s': %s",
 832                    exported_dir, strerror(errno));
 833         return -1;
 834     }
 835
 836     s->smb_dir = g_dir_make_tmp("qemu-smb.XXXXXX", NULL);
 837     if (!s->smb_dir) {
 838         error_setg(errp, "Could not create samba server dir");
 839         return -1;
 840     }
 841     smb_conf = g_strdup_printf("%s/%s", s->smb_dir, "smb.conf");
 842
 843     f = fopen(smb_conf, "w");
 844     if (!f) {
 845         slirp_smb_cleanup(s);
 846         error_setg(errp,
 847                    "Could not create samba server configuration file '%s'",
 848                     smb_conf);
 849         g_free(smb_conf);
 850         return -1;
 851     }
 852     fprintf(f,
 853             "[global]\n"
 854             "private dir=%s\n"
 855             "interfaces=127.0.0.1\n"
 856             "bind interfaces only=yes\n"
 857             "pid directory=%s\n"
 858             "lock directory=%s\n"
 859             "state directory=%s\n"
 860             "cache directory=%s\n"
 861             "ncalrpc dir=%s/ncalrpc\n"
 862             "log file=%s/log.smbd\n"
 863             "smb passwd file=%s/smbpasswd\n"
 864             "security = user\n"
 865             "map to guest = Bad User\n"
 866             "load printers = no\n"
 867             "printing = bsd\n"
 868             "disable spoolss = yes\n"
 869             "usershare max shares = 0\n"
 870             "[qemu]\n"
 871             "path=%s\n"
 872             "read only=no\n"
 873             "guest ok=yes\n"
 874             "force user=%s\n",
 875             s->smb_dir,
 876             s->smb_dir,
 877             s->smb_dir,
 878             s->smb_dir,
 879             s->smb_dir,
 880             s->smb_dir,
 881             s->smb_dir,
 882             s->smb_dir,
 883             exported_dir,
 884             passwd->pw_name
 885             );
 886     fclose(f);
 887
 888     smb_cmdline = g_strdup_printf("%s -l %s -s %s",
 889              CONFIG_SMBD_COMMAND, s->smb_dir, smb_conf);
 890     g_free(smb_conf);
 891
 892     if (slirp_add_exec(s->slirp, smb_cmdline, &vserver_addr, 139) < 0 ||
 893         slirp_add_exec(s->slirp, smb_cmdline, &vserver_addr, 445) < 0) {
 894         slirp_smb_cleanup(s);
 895         g_free(smb_cmdline);
 896         error_setg(errp, "Conflicting/invalid smbserver address");
 897         return -1;
 898     }
 899     g_free(smb_cmdline);
 900     return 0;
 901 }
 902
 903 #endif /* !defined(_WIN32) */
 904
 905 static int guestfwd_can_read(void *opaque)
 906 {
 907     struct GuestFwd *fwd = opaque;
 908     return slirp_socket_can_recv(fwd->slirp, fwd->server, fwd->port);
 909 }
 910
 911 static void guestfwd_read(void *opaque, const uint8_t *buf, int size)
 912 {
 913     struct GuestFwd *fwd = opaque;
 914     slirp_socket_recv(fwd->slirp, fwd->server, fwd->port, buf, size);
 915 }
 916
 917 static ssize_t guestfwd_write(const void *buf, size_t len, void *chr)
 918 {
 919     return qemu_chr_fe_write_all(chr, buf, len);
 920 }
 921
 922 static int slirp_guestfwd(SlirpState *s, const char *config_str, Error **errp)
 923 {
 924     /* TODO: IPv6 */
 925     struct in_addr server = { .s_addr = 0 };
 926     struct GuestFwd *fwd;
 927     const char *p;
 928     char buf[128];
 929     char *end;
 930     int port;
 931
 932     p = config_str;
 933     if (get_str_sep(buf, sizeof(buf), &p, ':') < 0) {
 934         goto fail_syntax;
 935     }
 936     if (strcmp(buf, "tcp") && buf[0] != '\0') {
 937         goto fail_syntax;
 938     }
 939     if (get_str_sep(buf, sizeof(buf), &p, ':') < 0) {
 940         goto fail_syntax;
 941     }
 942     if (buf[0] != '\0' && !inet_aton(buf, &server)) {
 943         goto fail_syntax;
 944     }
 945     if (get_str_sep(buf, sizeof(buf), &p, '-') < 0) {
 946         goto fail_syntax;
 947     }
 948     port = strtol(buf, &end, 10);
 949     if (*end != '\0' || port < 1 || port > 65535) {
 950         goto fail_syntax;
 951     }
 952
 953     snprintf(buf, sizeof(buf), "guestfwd.tcp.%d", port);
 954
 955     if (g_str_has_prefix(p, "cmd:")) {
 956         if (slirp_add_exec(s->slirp, &p[4], &server, port) < 0) {
 957             error_setg(errp, "Conflicting/invalid host:port in guest "
 958                        "forwarding rule '%s'", config_str);
 959             return -1;
 960         }
 961     } else {
 962         Error *err = NULL;
 963         /*
 964          * FIXME: sure we want to support implicit
 965          * muxed monitors here?
 966          */
 967         Chardev *chr = qemu_chr_new_mux_mon(buf, p, NULL);
 968
 969         if (!chr) {
 970             error_setg(errp, "Could not open guest forwarding device '%s'",
 971                        buf);
 972             return -1;
 973         }
 974
 975         fwd = g_new(struct GuestFwd, 1);
 976         qemu_chr_fe_init(&fwd->hd, chr, &err);
 977         if (err) {
 978             error_propagate(errp, err);
 979             object_unparent(OBJECT(chr));
 980             g_free(fwd);
 981             return -1;
 982         }
 983
 984         if (slirp_add_guestfwd(s->slirp, guestfwd_write, &fwd->hd,
 985                                &server, port) < 0) {
 986             error_setg(errp, "Conflicting/invalid host:port in guest "
 987                        "forwarding rule '%s'", config_str);
 988             qemu_chr_fe_deinit(&fwd->hd, true);
 989             g_free(fwd);
 990             return -1;
 991         }
 992         fwd->server = server;
 993         fwd->port = port;
 994         fwd->slirp = s->slirp;
 995
 996         qemu_chr_fe_set_handlers(&fwd->hd, guestfwd_can_read, guestfwd_read,
 997                                  NULL, NULL, fwd, NULL, true);
 998         s->fwd = g_slist_append(s->fwd, fwd);
 999     }
1000     return 0;
1001
1002  fail_syntax:
1003     error_setg(errp, "Invalid guest forwarding rule '%s'", config_str);
1004     return -1;
1005 }
1006
1007 void hmp_info_usernet(Monitor *mon, const QDict *qdict)
1008 {
1009     SlirpState *s;
1010
1011     QTAILQ_FOREACH(s, &slirp_stacks, entry) {
1012         int id;
1013         bool got_hub_id = net_hub_id_for_client(&s->nc, &id) == 0;
1014         char *info = slirp_connection_info(s->slirp);
1015         monitor_printf(mon, "Hub %d (%s):\n%s",
1016                        got_hub_id ? id : -1,
1017                        s->nc.name, info);
1018         g_free(info);
1019     }
1020 }
1021
1022 static void
1023 net_init_slirp_configs(const StringList *fwd, int flags)
1024 {
1025     while (fwd) {
1026         struct slirp_config_str *config;
1027
1028         config = g_malloc0(sizeof(*config));
1029         pstrcpy(config->str, sizeof(config->str), fwd->value->str);
1030         config->flags = flags;
1031         config->next = slirp_configs;
1032         slirp_configs = config;
1033
1034         fwd = fwd->next;
1035     }
1036 }
1037
1038 static const char **slirp_dnssearch(const StringList *dnsname)
1039 {
1040     const StringList *c = dnsname;
1041     size_t i = 0, num_opts = 0;
1042     const char **ret;
1043
1044     while (c) {
1045         num_opts++;
1046         c = c->next;
1047     }
1048
1049     if (num_opts == 0) {
1050         return NULL;
1051     }
1052
1053     ret = g_malloc((num_opts + 1) * sizeof(*ret));
1054     c = dnsname;
1055     while (c) {
1056         ret[i++] = c->value->str;
1057         c = c->next;
1058     }
1059     ret[i] = NULL;
1060     return ret;
1061 }
1062
1063 int net_init_slirp(const Netdev *netdev, const char *name,
1064                    NetClientState *peer, Error **errp)
1065 {
1066     struct slirp_config_str *config;
1067     char *vnet;
1068     int ret;
1069     const NetdevUserOptions *user;
1070     const char **dnssearch;
1071     bool ipv4 = true, ipv6 = true;
1072
1073     assert(netdev->type == NET_CLIENT_DRIVER_USER);
1074     user = &netdev->u.user;
1075
1076     if ((user->has_ipv6 && user->ipv6 && !user->has_ipv4) ||
1077         (user->has_ipv4 && !user->ipv4)) {
1078         ipv4 = 0;
1079     }
1080     if ((user->has_ipv4 && user->ipv4 && !user->has_ipv6) ||
1081         (user->has_ipv6 && !user->ipv6)) {
1082         ipv6 = 0;
1083     }
1084
1085     vnet = user->has_net ? g_strdup(user->net) :
1086            user->has_ip  ? g_strdup_printf("%s/24", user->ip) :
1087            NULL;
1088
1089     dnssearch = slirp_dnssearch(user->dnssearch);
1090
1091     /* all optional fields are initialized to "all bits zero" */
1092
1093     net_init_slirp_configs(user->hostfwd, SLIRP_CFG_HOSTFWD);
1094     net_init_slirp_configs(user->guestfwd, 0);
1095
1096     ret = net_slirp_init(peer, "user", name, user->q_restrict,
1097                          ipv4, vnet, user->host,
1098                          ipv6, user->ipv6_prefix, user->ipv6_prefixlen,
1099                          user->ipv6_host, user->hostname, user->tftp,
1100                          user->bootfile, user->dhcpstart,
1101                          user->dns, user->ipv6_dns, user->smb,
1102                          user->smbserver, dnssearch, user->domainname,
1103                          user->tftp_server_name, errp);
1104
1105     while (slirp_configs) {
1106         config = slirp_configs;
1107         slirp_configs = config->next;
1108         g_free(config);
1109     }
1110
1111     g_free(vnet);
1112     g_free(dnssearch);
1113
1114     return ret;
1115 }